Scots scientists follow where Doctor Who leads

FRANK URQUHART

SINCE it made its first appearance in the hands of Patrick Troughton in 1968, the sonic screwdriver has been as much an iconic part of the Doctor Who legend as the Tardis, Daleks and the Cybermen.

The all-purpose DIY tool of the future is capable of everything from opening doors and destroying aliens across the universe, to healing wounds and remotely operating the controls of the Tardis itself.

A replica of the sonic screwdriver

Now Scottish scientists have turned sci-fi fantasy into reality by developing the world’s first real-life sonic screwdriver.

Until now, ultrasound beams have been successfully used only to move objects forwards. But the physicists at Dundee University are the first in the world to make an object spin – essentially like the Doctor’s iconic gadget.

By using an ultrasound beam shaped like a helix or vortex, they have been able to spin a rubber disk as fast or as slow as they dictate – using the laws of physics which allow ice-skaters to spin faster when their arms are at their side or slower with their arms extended.

It now hoped the new device can be developed to help surgeons using ultra sound in the operating theatre.

Dr Mike MacDonald, a physicist at the university’s Institute for Medical Science and Technology, is one of the leading researchers behind the breakthrough, using equipment designed for MRI-guided focused ultrasound surgery.

He and his team used energy from an ultrasound array to form a beam that can both carry momentum to push away an object in its path and, by using a beam shaped like a helix or vortex, cause the object to rotate.

Dr MacDonald said: “Like Doctor Who’s own device, our sonic screwdriver is capable of much more than just spinning things around.

“This experiment… demonstrates a new level of control over ultrasound beams which can also be applied to non-invasive ultrasound surgery, targeted drug delivery and ultrasonic manipulation of cells.

“The machine lifts things and spins them at the same time.

“The spinning is to do with the conservation of angular momentum. If you think about ice-skaters who are spinning around they can make themselves go much, much faster by pulling their arms in and slow down by moving them out.”

Dr MacDonald said: “One thing we are interested in looking at is negative radiation pressure. It’s a little bit like the Star Trek tractor beam, where you can suck things towards you, instead of pushing stuff away.”